METHOD OF OILY FRACTION SELECTIVE REFINING Russian patent published in 1996 - IPC

FIELD: oil refining. SUBSTANCE: method involves countercurrent raw contacting adding to upper part of extractor in the presence of antisolvent which is fed to bottom part of extractor. Solvent is regenerated from raffinate and extractant solutions obtaining raffinate and extract. Raffinate is distilled off, vapor phase is obtained and after its cooling the first fraction of raffinate is obtained. Part of this fraction is added to extractor between raw and antisolvent feeding and at temperature not exceeding that of raw inlet to extractor. Liquid phase obtained at distillation off is removed as the second fraction of raffinate. EFFECT: improved method of refining. 9 tbl, 2 dwg